Optically-pumped solid-state lasers have been useful sources of coherent radiation for more than 20 years. In recent years, improvements in laser performance have resulted from the fabrication of semiconductor quantum-well structures. In a quantum-well structure, thin atomic layers of smaller energy bandgap semiconductor material, for example GaAs, are sandwiched between thin layers of wider bandgap material, for example Al.sub.x Ga.sub.(1-x) As, to form potential wells in the conduction and valence bands. Such wells restrict or limit carrier/electron movement to two dimensions. Quantum-well heterostructures generally exhibit more efficient luminescence intensities than bulk crystal heterostructures and therefore, have been incorporated into the active region of semiconductor laser devices.